CVE-2026-6767 | Other issue in the Libraries component in NSS

Other issue in the Libraries component in NSS. This vulnerability was fixed in Firefox 150, Firefox ESR 115.35, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.

Published: 2026-04-21 Last update: 2026-04-22 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-6767 is rated Low Risk (27/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.05%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-6767

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-23 0.03% 0.05% +0.02%
2 2026-04-22 — 0.03% —

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-6767

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 1.4 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2026-6767

GitHub Security Advisory for CVE-2026-6767

GHSA-38r2-pp9w-hfh6 · Severity: medium — Other issue in the Libraries component in NSS. This vulnerability was fixed in Firefox 150,...

OS Trackers for CVE-2026-6767

vendor priority summary link
debian not yet assigned CVE-2026-6767 not yet assigned priority: Debian including 4 source packages (firefox, firefox-esr, nss, thunderbird), 16 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 14, open 2. https://security-tracker.debian.org/tracker/CVE-2026-6767
redhat medium — https://access.redhat.com/security/cve/CVE-2026-6767
ubuntu medium CVE-2026-6767 medium priority: Ubuntu including 9 source packages (firefox, mozjs102, …), 49 status rows across 7 suites (bionic, focal, jammy, noble, questing, resolute, upstream): DNE 23, needs-triage 10, ignored 8, not-affected 7, needed 1. https://ubuntu.com/security/CVE-2026-6767

Affected software / configurations for CVE-2026-6767

Vendor Product Version Raw CPE
mozilla firefox < 115.35.0 cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*
mozilla firefox < 150.0 cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*
mozilla firefox >= 140.0, < 140.10.0 cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*
mozilla thunderbird >= 140.0, < 140.10.0 cpe:2.3:a:mozilla:thunderbird:*:*:*:*:esr:*:*:*

References for CVE-2026-6767

cvelogic Threat Intelligence